Attachment-plug.



No. 797,472 PATENTED AUG, 15, 1905.

G. B. THOMAS. ATTACHMENT PLUG.

APPLICATION FILED PEB.3,1905.

INVENTOR 560 0. am WW W WITNESSES ATTORNEYS numsw a mum on, Pnnwmnoummmm wlsumamu 0 c UNITED STAT iilS intiru enrich,

GEORGE E. THOMAS, OF BRlDG-FlUltl, CONN lilillilil'l, ASSIGNOR TITO Till) PERKINS ELECTRIC SWlT Ul-l MANUFAUlURlNU ()()l\ ll:bi.l\ Y, OF BitlDGlG- PORT, CONNECTICUT, A (JORPORAflllON OF (JONNEUlTltEUl.

Specification of Letters Patent.

Patented Aug. 15, 1905.

Application filed February 3, 1905. Serial No. 244,008.

To all whom it iii/(151 concern:

Be it known that I, (inonen B. T1 io As, a ci tizen of the United States of America, residing in Bridgeport, in the county of Fairlield, Eitate of Connecticut, have invented certain new and useful Improvements in Attachmerit-Plugs, of which the following is a specification.

The object of my invention is to construct a simple and efficient attachment-plug for elec trical connections.

in the accompanying drawings, Figure 1 is a vertical section of an attaclnnent-plug constructed in accordance with my invention. Fig. 2 is an inner face View of the detachable cap. Fig. 3 is an inner face view of the base. Figs. 4 to 8 show in a series of views the several parts detached of a modified form of attachment-plug, Fig. 4 being a side view of the cap, Fig. 5 a sectional view of the cup, Fig. 6 a sectional view of the ring-terminal, Fig. 7 a perspective view of the insulatingcore, and Fig. 8 a perspective View of the central terminal and securing-screw; and Fig. 9 is a perspective view of a detail detached.

lln the construction illustrated in Figs. 1, 2, and 3, A is the cap, of porcelain or other insulating material, with a central opening a for the passage of the conducting-wires, the bared ends of which are connected up to the terminal plates B B by the binding-screws 7) 7). Each plate B B carries a cylindrical contactpinU, ((l,) which is adapted to enter and make electrical contact with a split socket D, (D,) carried by the base. 1 form the body of this base in two parts E and it, of porcelain or other suitable insulating material. These two parts ll will call for convenience of identification the cup E and core l". The cup E is formed with two separated and independent chambers c and c on its outer face, of which the larger chamber 2 reaches to and beyond the center of the cup. Within the larger chamber is the split-socket contact D, which I prefer to form by bending up a stamped piece of brass, Fig. 9, comprising a base-plate (Z with two upright jaws enlarged at their upper ends (2 cl and there curved to form a split socket to receive the corresponding pin C of the cap. These enlarged upper ends thus forming the split socket leave shoulders rr, Figs. land 9, below the top 0f the socket, to engage the inwardly-bent ends oi spring-latches F on the cap when the latter is applied to the base, as shown in Fig. l. The split-socket contact .1) in the smaller chamber 0 is similar to the socket 1), except that it has a much shorter base, and it is similarly combined with the contact-pin U and latching-spring F. l The socket l) is secured in place in the bottom of its chamber r by means of a central screw G, which passes through the core It, at the outer end of which it is provided with a head and a dished washer w, forming there the central end terminal oi the plug. The socket D is secured in the bottom of its chamber 1 by means of a screw H, inserted through a hole in a 'llai'igejot' the threaded ring-terminal J and through a hole in the bottom of the cup E. The core i5 is recessed at 1', Figs. 1 and 7, to receive the head of this screw H. The ring-terminal J its over and is supported by the core E and is in electrical connection with the socket D through the screw H.

The upper ends or jaws of the split sockets D 1) have a certain amount of elasticity, and these ends of each socket are placed suliiciently near each other to leave an opening of slightly less diameter than that of the cylindrical pin U, (0",) which is, however, beveled at its lower end, Fig. 1, so that when the cap A. is pressed on the beveled ends of the pins U C will enter the jaws of their respective sockets and press them apart, making thus a perfect sliding contact. The springs F F, which as a matter of simplicity of construction are shown in electrical contact with the plates carrying the pins 0 U, are not relied on for electrical connections, but merely to mechanically aid in retaining the cap in place, and in fact one such spring will in some cases suilice.

in Figs. 4: to 8 I have illustrated my improvements in the construction of cup and core and connected parts as applied to a known type of attaclnncnt-plug, in which the cap A, Fig. l, carries two metallic legs a a with headed screws a and when the cap is litted down onto the chambered cup E, Fig. 5, these screws enter open jaws in the legs e c of the plates carried by the cup. These plates are secured in place and are electrically connected in the circuit by the same screws G and H, Figs. 6 and 8, as described with reference to Fig. l.

I claim as my invention 1. An attachment-plug, comprising a cap carrying terminals with a chambered cup of insulating material carrying contacts with which the cap-terminals make electrical connection, a ring-terminal secured to the other side of the cup and electrically connected with one of said contacts on the chambered side of the cup, a separate insulating-core and a central securing-screw electrically connected to the other contact on the chambered side of the cup.

2. An attachment-plug, comprising a cap carrying terminals with a chambered cup of insulating material carrying contacts with which the cap-terminals make electrical connection, a ring-terminal on the other side of the cup, a screw securing it thereto and to one of said contacts on the chambered side o1 the cup, a separate insulating-core and a central screw securing the core to the cup and to the other contact in the chambered side of the cup.

3. An attachment-plug, comprising a cap carrying terminals with an insulatingcup having two chambers on its outer face, contacts carried by the cup in said chambers and adapted to make connection with the cap-terminals, a ring-terminal secured to the other side of the cup and connected to one of the contacts in one of said chambers, a separate insulating-core and a central securing-screw electrically connected to the contact in the other chamber.

4C. The combination of the cap and chambered insulating-base of an attachment-plug with cylindrical contact-pins and latchingsprings on one part and jaws with enlarged curved upper ends forming split sockets and shoulders on the other part.

In testimony whereof I have signed my name to this specification in the presence of two subscribing witnesses.

GEORGE E. THOMAS. lVitnesses:

Ur. W. Goonnrnen, N. V. HARDER. 

